Kotliar, Serhii, Oleksandr Toporkov, and Tetiana Sidorova. “Special Force Training of Qualified Cross-Country Skiers of 18-20 Years Old in the Preparatory Period”. Slobozhanskyi Herald of Science and Sport, no. 2(82) (May 24, 2021): 37–43. Accessed August 17, 2024. https://journals.uran.ua/index.php/1991-0177/article/view/232358.